Secagem de sementes de cacau, em camadas finas, a 60°C e 80°C.

Abstract

This work was performed in the Storage Laboratory onthe Universitu of Viçosa ("Universidade Federal de Viçosa " U .F .V ., Minas Gerais). Thin laye r druing curves were plotted for fresh fermented cocoa beans, with drying air temperatures of 60° and 80°C and constant air flow of 35 m. m in -1. The drying curves were drawn for both temperatures, using averaged data of for repetitions . The schedule for the weighing of the beans was: every two minutes during the first half hour of dryin g ; everu five minutes between two hours and ten minutes and six hours; and every twenty minutes between six hours the end of each drying operation . Regression equations, from the analysis of the obtained data, described the moisture content as a function of drying time. The results showed the existence of two distincti drying periods. During the first thirty minutes of drying , the rate o f water removal from the beans was high both drying tempera tures (60° and 80°C ) . The superficial water layer of the beans was evaporated quickly and during this period the moisture content varied proportionally with the drying time. In the second period from the half hour to eleven hours for the 60°C and from the half hour to eight hours for the 80°C temperature, in was observed th at there was a delay of water movement by opposing internal forces . During this period the moisture content decreased exponentially , which gave an equilibrium at the end of the observed drying periods.